1. Field of the Invention
The invention resides in the field of light traps and more particularly relates to an improved light trap or light seal construction employing spring members and compressible light blocking strips.
2. Description of the Prior Art
There is a great variety of light traps used on photographic equipment, many of which are patented and form a body of art in this area. As films have become more and more sensitive, newer light traps have become necessary and the current extremely high speed Polaroid film necessitated the development of the device of this invention. Some prior light traps have involved the use of felt or other tufted materials arranged so that the exposure-controlling slide makes contact with this material and the tufts then act as a barrier to the light preventing exposure of the film. Another type of light trap utilizes a light seal composed of rubber or other resilient material pressing against the exposure-controlling slide similar to a window squeegee against a pane of glass and when the slide is removed, the rubber element then seals against the opposite member of the light trap. Further light traps have been developed in the area of fabric or other cushioning materials covering metal spring elements structured so that they are mounted transversely to the movement of the exposure-controlling slide and when the exposure-controlling slide is removed, the spring urges the fabric or cushion to close the guideway by making contact with the opposite member of the light trap.
All of the above styles of light traps, even though they worked quite well with lower speed films, have proved unsatisfactory in blocking light from the latest high speed films which are ten to thirty times more sensitive to light than the films in existence when the above mentioned light traps were first developed.